On Mon, 04 Jul 2005 21:49:46 GMT, "Jay Honeck"
wrote:

I recently rented an older 172, with a Nav-o-Matic relic. I've never flown
with one of those things, so I left it alone. For all I know, it's just as
reliable.

"Nav-O-Matic"??

Was there a coin slot, or had it been upgraded to accept dollar bills?

Nav-O-Matic seems to be different than the Tactair we have int he
club's '61 172. The Tactair is a wing-leveler that also tracks the
DG. It is all-pneumatic -- everything, including the servo motors,
runs off the vacuum system. Heading input comes from a special DG
with two knobs and two old-style rings, one above the other. You set
one ring like an ordinary DG and you set the other for desired
heading. Then the AP tries to make them match.

It's good for folding charts. After a while, it tends to hunt. There
are a couple of screws for adjusting damping factor, but on our
installation, one is only a rumor in the owners manual. If it exists,
it is behind so many other things in back of the panel, nobody can
locate it.

It's like the fellow said about women preachers. . . .

Don